Cut-off machine



June 27, 1939. Ml STRAWN ET AL 2,163,967

CUT-OFF MACHINE Filed Jan. 12, 1938 4 Sheets-Sheet 1 `une 27, 1939. LSTRAWN ET AL 2,163,967

CUT-OFF MACHINE Filed Jan. l2, 1958 4 Sheets-Sheet 2 June 27, 1939. Y M.L. STRAWN Er AL brrr-OFF MACHINE Filed Jan. l2, 1938 4 Sheets-Sheet 5NVENTOQS @War/'0n L. 5//020/1 @We/vander One/o//fe/z June 27, 1939. M.L. sTRAwN Er AL CUT-OFF MACHINE Filed Jan. l2, 1938 4 Sheets-Sheet 4Patented June 27, 1,939

UNITED STATES CUT-OFF MACHINE Marion L.

Rockford, IIL,

Strawn and Alexander Oberhoffken,

assignors to The Ingersoll Mill- Machine Company, Rockford. Ill., acorinc poration of Illinois Application January 12, 1938, Serial No.184,502 14 claims. (C1. zii-69) The invention relates to a cut-offmachine for severing successive lengths of material from a continuouslymoving portion of stock and has more particular reference to such amachine in which the stock is clamped to a movable'head carrying acutter which operates on the stock during movement of the two in unisonand is returned to a starting position following severance of the stock.

The general object is to provide a machine of the above character whichis simple in construction, reliable and safe in operation, whichcompensates automatically for variations in operating conditions such asthe rate of travel of the stock and the character of the work material,and which avoids placing any substantial strains on the mechanism bywhich the stock is formed and advanced past the machine.

` Another object is to provide a machine of the above character foroperating on stock which is moved downwardly in a vertical directiontogether with a novel means for synchronizing the feed of the cutterheadand that of the stock.

A more detailed object is to provide a novel mechanism forcounterbalancing the weight of the cutter head and for utilizing suchmechanism as a power actuator for returning the head to a startingposition.

A further object is to provide arrangement for 30 clamping the stock tothe traveling cutter head.

45 trations of successive steps in Still another object is to providefor disabling the automatic cycle control mechanism in the event thatthe cutter is not conditioned for proper operation.

Another object is to provide a novel safety control mechanism fordisabling certain of the operating parts in the event that the cut-oi!operation is not completed while the stock is moving through apredetermined allotted distance.

Other objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which Figures 1 to 4 inclusive arediagrammatic illusthe operation of a cut-oil machine embodying thepresent invention.

Fig. 5 is a side elevation of the cut-oi! machine.

Fig. 6 is a transverse sectional view taken along 50 the line 6-6 inPig. 5.

Fig. 7 is a schematic view and wiring diagram. Fig. 8 is a detailedsectional view of one of the valves included in the control apparatus ofFig. 7. For convenience of illustration of its various novel features,the invention has been shown herein as embodied in a machineparticularly adapted for use in severing lengths of stock from acontinuously formed bar of copper or the like as it leaves the castingfurnace. It will be understood, however, that the invention is adaptedfor operation on a wide variety of work pieces and that there is nointention to limit the invention to the particular applicationdescribed. On the other hand, the appended claims are intended to coverall modieations and alternative arrangements within the spirit and scopeof the invention.

A general understanding of the type of machine and operationcontemplated is afforded by areference to the diagrammatic illustrationsin Figs. 1 to 4 inclusive. The numeral l0 designates a solid cylindricalbar of cast copper discharged continuously through the outlet l2 in thelower end H of a suitable casting furnace. The cast bar or portion ofstock is advanced `c011- tinuously by two pairs of power actuatedrollers I3 engaging its opposite sides and operable at variable speedsaccording to furnace operating conditions.

The present machine operates automatically to cut oil the stock leavingthe furnace into billets 8 of any desired lengths, and this withoutinterfering with the continuity of the casting or other process by whichthe stock is formed. Generally stated, the machine comprises a tool headi4 mounted for movement lengthwise of the formed bar I 0 and carrying atool I5 for cutting off the bar. When a predetermined length of bar hasbeen discharged from the furnace, the lower or free end engages a tripdog Il which initiates an automatic cycle of the machine by causingactuation of a mechanism i6 for clamping the bar .and tool head togetherfor movement in unison. At the same time, the feeding of the tool I5into the bar is initiated. As the severing operation continues, the toolhead i4, together with the o saw and clamping mechanism is moveddownwardly as shown in Fig. 3 at a speed corresponding to the rate offormation of the bar. Severance of the bar is normally completed beforethe tool head has advanced a distance equal to the length of the barbeing cut oiI. In response to complete cutting of the bar, the saw I5 isretracted as shown in Fig. 4 and the clamping mechanism i8 released.Thereupon, the head Il is returned to its initial position. When thecut-oil end of 'the-bar l0 again strikes the dog l1, the cycle isrepeated.

The machine selected for purposes of illustration includes a fixed bedIt disposed below the furnace Il and supporting four vertical columns orposts I9 on which the saddle I4-is mounted for vertical slidingmovement. the upper ends of the columns I8 carries the stock advancingrollers I3 together with a power actuating mechanism therefor includingan electric driving motor 2|. This motor may be controlled by suitablemechanism (not shown) associated with the stock molded in the furnace IIso that the stock will be advanced at a rate commensurate with theoperating capacity of the furnace, this rate being adjustableautomatically or manually.

The tool head I 4l includes a generally rectangular open-center frame I4disposed horizontally and slidably mounted on the vertical columns I9.'I'he tool I5 which comprises a diskshaped saw is fast on a verticalshaft I5n journaled in bearings which are supported by a carriage 22.The latter is mounted for endwise sliding movement on a pair of spacedhorizontal guides 23 extending lengthwise of the frame I4* and securedto opposite ends ofthe latter. An electric motor 24 mounted on thecarriage 22 drives the saw I5 through the medium of belts 25.

Movement of the saw supporting carriage 22 toward and away from the workpiece or stock I0 is effected by means of hydraulic mechanism includinga piston 26 slidable in a cylinder 21 and secured to a rod 26* havingits outer ends secured to a yoke 28 on the carriage 22. As isdiagrammatically illustrated in Fig. '1, pressure fluid is supplied tothe cylinder 21 by a pump 29 driven by an electric motor 30, the flow offluid being controlled by the control valve. 3| which is in turnactuated through the medium of a pair of oppositely acting valvesolenoids V1 and V2. When the solenoid V1 is energized, the valve 3| isshifted to cause a flow of fluid from the pump 29 through conduits32--33, valve 3|, and conduit 34 to the outer end of piston 26. The sawI5 is then advanced toward the bar I0. The rate of such feed iscontrolled by the escape pressure fluid from the forward end of thecylinder through conduit 35 to a sump 44, the rate of escape beinggoverned by a manually adjustable valve 35. Changes in setting of thisvalve regulate the feed rate. A check valve 35b permits the ow of fluidfrom the valve 3| through the conduit 35 to the forward end of thecylinder for returning the saw but forces the fluid exhausted from theforward end of the cylinder 21 through the valve 35".

Energization of the other solenoid Vi and deenergization of Vi shiftsthe member of the valve 3| to eifect a rapid return movement of the sawcarriage 22. When the valve member is so shifted, pressure fluid fromthe pump 26 is delivered through conduits 32, 33, valve 3l, conduit 35,valve 35", and conduit 35 to the forward end of piston 26 withoutrestriction by the orifice 35.v Similarly, fluid is drained to the sump44 without restriction from the rear end of the cylinder 21 through aconduit 34.

The clamping mechanism I6, which preferably is actuated hydraulically,includes a pair of spaced clamping jaws 36 (Fig. 6) fixed on the saddleI4 and arranged respectively above and below the saw I5. These Jawscooperate with a pair of opposed movable jaws 31 secured to the ends ofrods on pistons 33. These pistons are slidable in cylinders 39 securedto the outer end of the tool head frame I4. The cylinders 39 are alsosupplied with pressure fluid from the pump 29, the supply being underthe control of a valve .40 operated by a pair of oppositely actingsolenoids V: and V4. When the solenoid V; is en- A housing 20 onergized, the valve member is shifted to permit the flow of pressurefluid from the pump 29 through conduits 32-33, valve 40, and conduit 4Ito the outer ends of the pistons 38 hereby the jaws 31 are moved intoclamping engagement with the stock I0. Pressure fluid is exhausted fromthe inner faces of the pistons 38 through conduit 42, valve 40, andconduit 43 to a sump 44. Similarly, when the solenoid V4 is energized, avalve member is shifted in the opposite direction to permit the flow ofpressure fluid from the pump 29 through conduits 32--33, valve 40, andconduit 42 to the inner faces of the pistons 38 thereby retracting thejaws 31 and unclamping the bar III. In such position of the valve, fluidis exhausted from the outer faces of the pistons 38 through conduit 4I,valve 40, and conduit 43, through which it returns to the sump 44.

By employing clamps engageable with the stock below as well as above theline of severance, the lower endportion of the stock is held rigidly inplace throughout the entire period of active engagement of the cutterand the stock. As a result, movement of the lower end of the stock whichmight pinch the cutter or otherwise interfere with its operation iseliminated and a clean cut is produced.

In order to avoid objectionable strain on the clamping mechanism andpossible slippage which might result if the tool head I4 were supportedentirely through the medium of the clamping mechanism and the clampedbar, means is provided for counterbalancing the weight of the tool head.Preferably, this means also performs the additional function of raisingthe tool head to its upper or starting position upon the completion ofthe stock severing operations. The counterbalancing means includes ahydraulic piston 45 (Fig. 5) slidably mounted in a vertical cylinder 46fixed to the bed I8. The piston is on the lower end of a vertical rod45a the upper end of which is attached to the tool head frame I4. Whenthe tool head is in the uppermost or starting position shown in Figs. 5and '1, the lower portion of the cylinder 46 is filled with pressurefluid which is permitted to drain from the cylinder at a controlled ratein such manner that the tool head I4 will descend at a speedsubstantially equal to the rate of downward movement of the stock l0.The clamping mechanism I6 which engages the stock prevents any slightrelative movement between the head and stock which might otherwise occurdue to variations in rate of movement or slight inequalities in therates, thereby preventing undue strain on or possible breakage of thesaw.

As shown in Fig. 7, pressure fluid is supplied to the cylinder 46 fromthe pump 29 through a control valve 41 actuated by a pair of oppositelyacting solenoids Vs and Vs. When the solenoid V5 is energized, the valve41 is shifted to permit the flow of fluid from the pump 29 throughconduits 32-33, valve 41, a conduit 50, a check valve 50, and conduit 48to the lower side of the piston 45, thus forcing the same upwardly andraising the carriage I4. The construction of the valve 50 is such (seeFig. 8) that fluid entering the inlet 50* will force a movable member5I)b into the position shown, open the spring closed valve-'element 60and ilow into the conduit 48. At the same time, uid is exhausted fromthe upper end of the piston to the sump 44 through a conduit 49 (Fig.'1). Upon the energization of the other solenoid Va and deenergizationof Vs, the supply of pressure fluid to the lower end of the cylinder 46is cut 01T and the fluid in the cylinder is permitted to drain into thesump at a rate controlled by the valve 50 which may be adjusted manuallyby turning a knob 50". Fluid entering the valve through the conduit 48forces the member 5IIb to the right thereby opening the outlet portleading to the conduit 48* to a degree determined by the valveadjustment. The conduit 48'I leads through the conduit 4 9 to the sump.Preferably, the valve is so adjusted that the pressure acting upwardlyon the tool head is slightly less than the weight of the head. In thisway, only the unbalanced weight ofthe head is imposed upon the clampingmechanism and the feed rolls.

Automatic control of the cut-oi! machine through repeated cycles ofoperation is effected by means of an electrical control systemassociated with the valve actuating solenoids. As best shown in Fig. '1,this system embodies manualy operable push button switches S1 and S: forstarting and stopping the machine in response to their respectivemomentary closure as well as a similar pair of start and stop switchesS3 and S4 for the hydraulic pump motor 30,' and an emergency stop switchSs provided with a manually operable reset button 5I. In addition tothese manual switches, the system also includes a limit switch LS1actuated by the dog I1 when the latter is engaged by the work piece I0,a pair of limit switches LS1 and LS; actuated by dogs 52 and 53 attachedto a rod 52* carried by the horizontally movable saw carriage 22, asecond pair of limit switches LS4-LS5 actuated by dogs 54--55 attachedto the tool head I4, and a limit switch LSs actuated by a dog 56 on oneof the movable clamping jaws 31. These various manually and dog operatedswitches control the several valve actuating solenoids through themedium of a series of control relays R1 to R1 inclusive. The sets ofcontacts for these various relays have been designated as RC with asubscript which includes as its rst number the corresponding relaysubscript number and as its second number a designation of the set ofcontacts. Current is supplied to the pump moto: 30 and saw driving motor24 from supply lines L1, L2 and La while the lines Li and La also supplythe various control and valve actuating solenoid circuits.

The automatic control system when once set in operation is adapted tomaintain the machine operating through repeated cycles each includingthe steps of (l) actuation of the clamping mechanism I6 to grip themoving bar of stock I0; (2) initiation of the downward movement of thetool head I4 by means of the hydraulic piston mechanism 45; (3)initiation of the forward movement of the saw I5 into engagement withthe stock; (4) retraction of the saw IB out of engagement with the stockupon completion of the severing operation; (5) unclamping of themechanism I6; and (6) return of the saddle I4 to its initial position.The frequency with which the cycle is repeated is of course a functionof the rate of movement of the stock.

In order to prepare the machine for operation, the pump motor startingswitch Sa is closed momentarily, thereby actuating the pump motorcontrol relay Rv (through a circuit this relay being maintained in itsclosed position by its sealing contact R1C1 which complete a shuntcircuit around the momentarily closed starting switch Si. This actuationof the relay R1 also closes its main contacts R'rCz, thereby connectingthe pump motorlii to its three phase supply lines L1, In, La andstarting the same in operation. The driving motor 2I ior'the stockadvancing rollers I3 is controlled through the medium of a separatecircuit.

The automatic cyclic operation of the cut-oil machine is initiated by amomentary closure of the cycle starting switch S1 which serves toactuate the self-sealing main control circuit relay R1 (through acircuit Closure of the main contacts RiC: of the relay R1 connects thesaw driving motor 24 to the supply lines Li-La-Lc, thereby starting thesame in operation. It will be noted that the energizdng circuit for therelay Ri includes contacts R401 of the normally energized emergency stoprelay R4, which in turn includes in its energizing, circuit(L1-R4-81-Ss--68-La) the emergency stop switch S5 so that the saw motorcannot be started unless the emergency stop switch is closed and therelay R4 energized.

After the machine has thus been conditioned for operation, the automaticcycle is initiated by closure of the switch LS1 which occurs when thelowermost end of the stock I has been advanced into engagement with andhas actuated the dog I1. This causes energization of the clamping relayRe (through a circuit which relay in turn energizes the solenoid valveactuator Va (through a circuit The valve 40 is thus operated to permitthe ilow of pressure fluid from the pump 28 through the conduit 4I tothe outer ends of the pistons 38 which shift the movable clamping jaws31 for# wardly into engagement with the stock and iirmly clamp the toolhead I4 to the continuously moving bar of stock.

The second step in the cycle oi operation, namely, downward movement ofthe tool head in synchronism with the moving bar III. is of courseinitiated substantially simultaneously with completion of the clampingoperation. 'Ihe control circuits are so arranged that the movement ofthe clamping jaws 31 into clamped position will also serve to initiatedownward movement of the piston 45 of the counterbaiancing mechanism ithrough the medium of control relay Rz. Thus,

as the clamping jaws 31 move into clamped position, the dog i on one ofthe jaws closes switch LSs, thereby energizing the relay Ra (through acircuit LiRz-14-LSc-15-La). Energization of this relay in turn serves toenergize the valve operating solenoid Vs (through a circuitLi-16-R2Ci-11-Vof-13-In) thereby shifting the control valve 41 to permitpressure fluid to be exhausted from the lower side of the piston 45.With the valve 50 adjusted as described above, the tool head ispermitted to descend at a rate substantially equal to cylinders to buildup and cause effective gripping of the bar following actuation of theswitch LSe. Thus, the counterbalance is conditioned for downward feedingof the tool head at a time not later than the full or effective clampingof the bar. As a result, clamping of the head to the stock and startingot the head movement occurs without shock or danger of displacing thebar relative to the feed rolls I3.

Closure of the relay R2 in response to clamping of the bar alsoinitiates the -third step in the cycle of operation, namely, the forwardfeed movement of the saw i5.v Thus, closure of relay Rz causes thevalve'actuating solenoid V1 to be energized (through a circuitLl-is-Rici-.n-mcl-uL-vl-n-w to shift the control valve 3l in order toadmit* pressure iiuid to the outer end of the piston 26 and therebycause an advancing movement of the saw supporting carriage 2,2 at arelatively slow feed rate controlled by the` regulating orifice 'I'herotating saw I5 thus cuts of! a length of the bar predetermined by thedistance the dog l1 is spaced, from the clamping mechanism i6 in theuppermost position of the latter.

Upon the completion of the severing operation the fourth step in thecycle of operation, namely, retraction of the saw i5 out of engagementwith the bar, is initiated by closure of switch LS:

which occurs when the dog 53 on the saw carriage '22 engages thefollower by which the switch is actuated. 'Ihe self-sealing controlrelay R: is thus energized through a circuit L1-Rs-1 9-LS2-80--8i--RzCs-B 2In) which deenergizes the solenoid V1 by opening the contactsR101 and energizes the opposed solenoid V2 (through a circuit Thisshifts-the valve 3i to admit pressure. iluid to the cylinder 21 foreffecting a rapid return movement of the saw carriage 22 relative to thetool head. The relay seals itself in closed position by means ofcontacts RcC4 in shunt with LS1. After the saw l5 has cleared the barI0, the clamping mechanism is released for the fifth step in the cycleof operation. The release of the clamping mechanism is initiated inresponse to complete retraction of the saw carriage 22 whereupon a dog52 closes the switch LSa thereby energizing the relay R5 (through acircuit for the clamp valve solenoid V3 by the opening of its contactsR501 and energizes the associated solenoid V4 by closure of its contactsRsCa through circuit L1-89-RsC2-90-V4-13-La). Energization of thesolenoid V4 and accompanying deenergization of the solenoid-Va serve toshift the control valve so that the pistons 38 retract the clamping jaws31 thereby disconnecting the tool head from the bar III. The severedportion of the bar thus falls free. As an incident to this, the tripswitch LCr is allowed to open thereby deenergizing the relay Re.

The sixth and iinal step in the cycle of operation, namely, return o!the tool head i4 upwardly to its initial position is initiated inresponse to unclamping. Thus, as the movable jaws 31 reach their fullyretracted position, the dog 58 permits theswitch LSe to open againthereby interrupting the energizing circuit for relay Ra which for thesolenoid Vs associated with the control valve 41, the solenoid Va beingsimultaneously deenergized by opening of the relay contacts The' valve41 is thus conditioned to admit pressure fluid to the bottom of thepiston so that the tool head is raised to its initial position, thismovement being arrested when the piston 45 contacts the upper end of thecylinder 46.

It will be noted that the deenergization of the relay Re which resultsfrom opening of the switch 1.5 during unclamping also causesdeenergization of relay R: by the .opening of the contacts B2C:interposed in the sealing circuit of the relay R3. In turn,deenergizattion of the relay R.: opencircuits the relay Rs since thecontacts RsCs are included in the energizing circuit of the relay Rs.This dropping out of the relay R5 does not, however, cause a re-clampingmovement of the jaws 31 since th'e relay Re has in the interim openeddue to the opening of switch LS1 as described above when the severed andunclamped work piece falls free. In general then it will be seen thatthe relays Rz, Rs, Rs and Re are all opened at the end of the unclampingmovement ofthe Jaws 31 so that the circuits are conditioned for arepetition of the cycle described upon a reclosure o f the dog operatedswitch LS1. Only the main relay R1, the emergency control circuit R4,and the pump driving motor relay Rv remain closed and these relays arenormally maintained in their closed positions during the entireoperation of the machine.

Means is provided which operates automatically to disable the cyclecontrol mechanism and thereby prevent the execution of a cycle in theevent that the switch mechanism for energizing the saw motor is notconditioned for operation of the motor. In the present instance, thismeans includes the switch Ri--Cz which is interposed in the energizingcircuit for the solenoid-V1 which controls the' first step in a cycle.In the event that the relay R1 is not energized and the switch Ri-Ca isthereby held open indicating that the saw motor 24 is not operating,the-solenoid Va will remain deenergized when the normal cycle startingswitch LS1 becomes closed by the, advance end ofthe stock. By thusdisabling the cycle control mechanism, any possibility of injury ofvthesaw or other parts is efiectually eliminated.

Normally, the saw will cut oil the bar i0 and be retracted before thepiston 45 reaches the lower end of the cylinder 46. In the event,however,

that the bar is not completely severed during the interval thusallotted, provision is made for retracting the saw and unclamping thebar so that no damage will result to the machine due to over-travel ofthe tool head. For this purpose, a dog carried by the tool head i4 isarranged to open a switch LS4 and closethe associated switches LSs andLSv when the head reaches the lower extremity of its safe path oftravel. The opening of the switch L84 breaks the sealing circuit of thesaw motor relay R1 thereby causing its contacts R103 toY open and thesaw motor to be stopped. Similarly, the closing of the switch Lenergizes the clamping mechanism control relay Rs (through a circuitL1-Rs-85-LS5-66-Ia thereby closing its contacts RsC: and opening its 30to stop the saw motor contacts RaCi to respectively energize theunclamping solenoid V4 and deenergize the clamping solenoid Va. Theswitch LS1 closes at the same time as LSs and completes a circuit to 5rapidly return the saw. Thus, when the switch LS1 closes, the relay R3is energized which closes the contact RaCz to energize the solel noidVn. The valve 3| is thereby shifted to direct uid into the forward endof the cylinder 21 to return the saw. As .previously described, thereturn of the clamp 31 opens the switch LSs to deenergize Rz and closethe switch R2C4 which en- 15 ergizes the solenoid Vs and causes theupward return of the saddle. Deenergization of R1 also opens theenergized contacts R102 which prevents the solenoid Vs from beingenergized until the start switch S1 is again depressed. The start- 20ing switch S1 is restored to effectiveness as soon as the saddle reachesits upper limit where the dog 54 closes the switch L84 and opens L86 andLS'I. 5

The machine may be stopped at will at any 25 time by opening theemergency stop switch S5 whichinterrupts the energizing circuit forrelay Ri. This deenergization of the relay R4 causes its contacts R401to be opened thereby breaking the sealing circuit for the saw motorrelay R1 and also closes its contacts R40: to complete an alternativeenergizing .circuit for the relay Rs (thrOugh Li-Ra-T 9-95-R4C3-96-Lcl.35 which in turn causes solenoid V1 to be deenergized and V2 to actuatethe valve 3i for a retractive movement of the saw carriage 22 asheretofore described. The opening of contacts RAC: in the energizingcircuit of the relay Rs prevents 40 its reenergization, however, untilthe saddle has lowered to the position where the dog 55 closes theswitch L85 which again energizes Rs and causes unclamping. The saddleremains in its lowered position until the reset button I is 45 depressedas the opening of contacts R404 interrupts the circuit of the saddlereturn solenoid Vs.

The machine may be similarly stopped at will by the momentary opening ofthe stop switch Sz 50 which also interrupts the sealing circuit of thesaw motor relay R1, s We claim as our invention: f 1. A machine forcutting a continuously moving length of stock successively into longitu-55 dinal sections of predetermined lengths, said machine having, incombination, a head movable longitudinally of the stock, stock clampingmeans on said head, means responsive to movement of the previouslycut-off end of the stock to a pre- 00 determined point past said head toactuate said clamping means, a cutter on said head operable duringmovement thereof with the clamped stock to cut of! the stock, meansresponsive to comlplete severance of the stock by said cutter to re- 65tract the cutter out of engagement with the stock and then release saidclamping means, and independent means operable automatically in responseto movement of said head to a predetermined position beyond its normalrange of move- 70 ment to eiect withdrawal of said cutter fromengagement with the work and release said clamping means.

2. A machine for cutting a continuously moving length of stocksuccessively into longitudinal 15 sections of predetermined lengths,said machine having, in combination, a head movable longitudinally ofthe stock, stock clamping means on said head, means responsive tomovement of the previously cut-of! end of the stock to a predeterminedpoint past said head to actuatev said 5 clamping means, a cutter on saidhead operable during movement thereof with the clamped stock to cut oithe stock, and means operable automatically upon failure of said cutterto sever the stock during movement of said head to a pre- 10 determinedpoint to retract said cutter out of engagement with the stock andrelease said clamping means.

3. A machine for cutting of! successive longitudinal sections from alength of stock moving continuously in a downward direction, saidmachine having, in combination, a vertically movable tool head, a poweractuated cutter thereon,

a vertical hydraulic cylinder, a piston in said cylinder connected tosaid head, means for restricting the ow of pressure uid from saidcylinder at a controlled rate such as to cause downward movement of saidhead substantially in synchronism with said stock, means on said headfor clamping the stock and head together during operation of said cutteron the stock, and means for supplying pressure fluid to said cylinder toraise the head following cutting oil of the stock.

4. vA machine for cutting ofi successive longitudinal sections from alength of stock moving continuously in a downward direction, saidmachine having, in combination, a vertically movable tool head, a poweractuated cutter thereon, means on said head for clamping the stock andhead together during operation of said cutter on the stock, andhydraulic means for substantially counterbalancing -the weight of saidhead during downward movement thereof.

5. A machine for cutting off successive longitudinal sections from alength of stock moving continuously in a downward direction, saidmachine having, in combination, a vertically movable tool head, a poweractuated cutter thereon, means on said head for clamping the stock andhead together during operation of said cutter on the stock, hydraulicmeans for at least partially counterbalancing the weight of said headduring downward movement thereof, and means to actuate said hydraulicmeans to raise said head to starting position.

6. A machine for cu ting of! successive longitudinal sections from alength of stock moving continuously in a downward direction, saidmachine having, in combination, a tool head guided for vertical movementadjacent and parallel to the advancing stock and tending to movedownwardly by gravity, a power actuated cutter carried by said head andmovable relative thereto across the path of the stock to cut oil! theleading end portion of the latter. mechanism releasably opposingdownward gravitational movement of said head and overcoming the weightthereof to hold the head in an upper starting position. means on saidhead for clamping thelatter and said stock together for movemlent of thetwo in unison, means responsive to the movement of said stock foractuating said clamping means and substantially simultaneouslydecreasing the opposing 1 force exerted by said mechanism whereby thelatter operates `to counter-balance at least a substantial proportion ofthe weight of said head during downward movement thereof.

'1. A machine for cutting oi successive longi tudinal portions from alength of stock moving continuously and endwise in a downward direction,said machine having, in combination, a tool head guided for verticalmovement adjacent and parallel to the advancing stock and tending tomove downwardly by gravity, a power actuated cutter carried by said headand movable relative thereto across the path of the stock to cut off theleading end portion of the latter, mechanism releasably opposingdownward gravitational movement of said head and overcoming the weightthereof to hold the head in a starting position, means on said head forclamping the latter and said stock together for movement of the two inunison, and means responsive to the movement oi said stock for actuatingsaid clamping means and releasing said mechanism substantiallysimultaneously.

8. A machine for cutting oi! successive longitudinal sections from a`length of stock moving in a downward direction, said machine having, incombination, a tool head guided for vertical movement adjacent andparallel to the advancing stock and tending to move downwardly bygravity, a, power actuated cutter carried by said head and movablerelative thereto across the path .of the stock to cut oil the leadingend portion of the latter, piston and cylinder elements containingpressure iluid and coacting to oppose downward gravitational movement ofsaid head and overcome the weight thereof whereby to hold the head inanupper starting position, means on said head for clamping the latter andsaid stock together for downward movement in unison, means responsive tothe movement o'f said stock for actuating said clamping means andreleasing the fluid in said cylinder, and manually adjustable means forregulating the flow of fluid out of said cylinder to cause a controlledcounterbalancing enect to be exerted on the head throughout the downwardmovement thereof.

9. A machine for cutting oil' successive longitudinal sections from alength of stock, said machine having, in combination, means engaging thestock and feeding same endwise in a downward direction at a variablycontrolled rate, a tool head guided for vertical movement adjacent andparallel to the advancing stock and tending to move downwardly bygravity, a power actuated cutter carried by said head and movablerelative thereto across the path of the stock to cut oil the leading endportion of the latter, means on said head for clamping the latter andsaid stock together, mechanism adapted, when rendered operative, toexert an upwardly directed force on said head and thereby counterbalanceat least a substantial portion of the weight of said head so that theforce required to be exerted by said feeding means to advance the headwhen the head and stock are clamped together is only the differencebetween the weight of the head and said upwardly directed force, landmeans respon'- sive to the movement of said stock for actuating saidclamping means and rendering said mechanism operative.

10. Alcut-ofl' machine for severing successive lengths from a movingportion of stock comprising, in combination, a tool head mounted formovement along the path of the stock, a power actuated cutter mounted onsaid tool head for feeding movement transversely of said path to cut oi!the stock, two power actuated clamps carried by said tool head andengageable with the stock on opposite sides of said cutter to clamp thestock to the head for movement with the latter, means responsive tomovement of a predetermined length of stock past said cutter to causecutter, and means responsive to and conditioned.

upon full retraction of said cutter out of engaging relation withrespect to the stock to unclamp.

the stock from said head and return the latter reversely along said pathto starting position.

l1. A cut-od machine for severing successive lengths of material from amoving portion of stoclr comprising, in combination, a tool head mountedfor movement along the path of the stock, clamping means engageable withthe stock at points spaced along the latter to clamp such points rigidlyto the head for movement of the latter with the stock, a power actuatedcutter mounted'on said tool head for feeding movement transversely ofsaid path to cut oil.' the stock along a line of severance disposedbetween said points of clamping, means operable by movement of saidcutter completely through the stock to initiate automatic retraction ofthe cutter, and means responsive to and conditioned upon movement ofsaid cutter out of engaging relation with respect to the stock torelease `said clamping means and free the stock from said head.

l2. A cut-oiI machine for severing successive portions of vstock from alength of stock moving downwardly continuously in an endwise direction,said machine comprising, in combination, a tool head mounted forvertical movement along the path of the stock, a clamp engageable withthe stock to clamp the latter rigidly to the head for movement of thelatter with the stock, a power actuated cutter mounted on said tool headfor feeding movement transversely of said path to cut ofi' the stockalong a line of severance disposed below said `olarrrp, means operableby movement of said cutter completely through the stock to initiateautomatic retraction of the cutter, means conditioned upon movement ofsaid cutter out of engaging relation with respect to the stock torelease said clamp and free the stock from said head, and an auxiliaryclamp applied and released automatically and operable during engagementof said cutter with the stock to grip the latter at a point disposedbelow but adjacent said line of severance and clamp the lower endportion of the latter rigidly against movement relative to said head.

13. A cut-off machine for severing successive longitudinal portions froma moving length of stock, said machine having, in combination, a toolhead mounted for movement along the path of said stock, a power rotatedcutter mounted on said head for movement relative to the headtransversely across said path, a power actuator for feeding andreturning said cutter across said path, a clamp for rigidly connectingsaid head to the stock for movement of the two in unison, a

,power actuator for applying and releasing said starting position tooperate said actuators whereout of said path to operate said clampactuator and said operator to release said clamp and immediately intiatereturn of said head to said starting position.

14. A cut-oi machine for severing successive longitudinal portions froma moving length of stock, said machine having, in combination, a toolhead mounted for movement along the path of said stock, a rotary cuttermounted on said head for movement forth and back across said path, anelectric motor for rotating said cutter, a clamp for connecting saidhead to said stock, individual power actuators respectively operable toapply and release said clamp, to advance and return said cutter relativeto said head and to return the head to starting position in a. directionreverse to stock movement, mechanism automatically responsive to theadvance of a predetermined length of stock past said cutter to causesaid actuators to execute an automatic cycle including, in succession,clamping of the stock, advance o! the head with the stock, feeding o1'the cutter across said path, return of the cutter out of said path,release of said clamp, and return of said head to starting position,means controlling the application of current to said cutter motor, andautomatically operating means to disable said mechanism againstinitiation of said cycle except when said last mentioned means isconditioned for the application of current to said motor.

MARION L. STRAWN.

AIEXANDER OBERHOFFKEN.

